Circuit interrupter



C. LE G. FORTESCUE AND F. C. BANKER.

CIRCUIT lNTERRUPTER.

Arrucmoa mnu'oct. 11. 1918.

Patented Aug. 29, 1922.

WITNESSES:

WMJIA INVENTORS Char/e: Le Farfeicue Fredegc C Han/rer ZTTURNEY ingUNITED STATES PATENT UFiFlCE.

CHARLES LE e. ron'rns'cun, or rrrrsnnnsmf AND FREDEBIC c. I-IANKER, orWILKINSBURG, PENNSYLVANIA; assmnoas TO WESTINGHOUSE nrnc'rmc aMANUFACTURING COMPANY, a CORPORATION or PENNSYLVANIA.

CIRCUIT INTERRUPTEB.

To all wlwmit may concern:

Be it known that we, CHARLES Ln G.

of Pittsburgh, in the county of Allegheny and State of Pennsylvania, andFREDERIGC. HANKER, a citizen of theUnited States, and a resident ;ofWilkinsburg State of ilennsylvania, have invented a new and useful.Improvement. vin Circuit. Inter,- rupters, of which the-following is aspecification. 1 i

Our invent'onrelates to circuit interrupt ers andparticularly toquick-acting interrupters: i 1 One object of our invention is toprovidemeans for interrupting a circuit in anticipation of an-o'verloadthereon.

. Another object of our invention is topr ovide a circuitinterrupter-actuating device thatshall be :so controlled-directly fromthe circuit that :its time of Operation shall be relatively short.

A further. object of our invention is to provide a circuit-interruptingdevice, of the above-indicated character, that shall-be simple and,inenpensiveto construct and accurate injits operation. i I .Inpracticing our invention we provide, a circuit interrupter-and anelectromagnet comprising a stationary core member having' an air gapthereim'an armature that normally bridges the air gap and is operativelyconnected )to the circuit interrupter, a spring for actuating thearmature to its open position, a windin for so energizing the stationarycore mem eras to normally hold the armature in its-closed position, and'a windoperatively connected to-the circuit and so disposedwith respectto the armature that, when the current in the direct-current circuitchanges quickly, by reason of a ground or short circuit thereon,suflicient current will induced in the winding to divert the 'fiux fromthe armatureithrough the air gap in the stationary core member and thuspermit the spring to quickly open the interrupter. Since theimpulse'current that is'setnpis caused by' the rapid change The singlefigure of the accompanying Specification of Letters Patent.

in the county of Allegheny rand Patented Aug. 29, 1922.

Application filed October 17, 1918. Serial No. 258,554.

drawing is a diagrammatic view of a directcurr'entcircuit embodying ourinvention.

-A-direct-current circuit 1 is supplied with energy from a source 2 ofelectromotive force and is provided with a circuit'interrupterfi havingan actuating and controlling device 4:. v

A devices comprises a sta netizable, core member 5 of substantiallyrectangular shape having an air gap 6 m;

oneieg thereof an armature 8 thatis pivotallymounted, at a point 9 onthe corememher 5, and an actuating Winding 7 that is connected in' shuntrelation to the circuit 1. for actuating the armature 8 to such positionasto open the interrupter 3 under predetermined conditions. A winding 12is disposed around the armature 8, and iscon nected, through a resistor13, to the terminals of a series transformer 14 with which the circuit-1 is provided. A r -Since the-armature 8 is adapted to bridge the airgap 6 under nornial conditions, the flux set up by'the winding 7 willtraverse the armature 8 and three legs of the core member 5 to therebyhold the interrupter 3 in its closed position. When a' short circuit orground occurs on the circuit 1. the voltage ofthe circuit will changequickly and thereby induce voltage in thetransformer 14 that will causesuflicient current to traverse the Winding 12 to set up a flux inopposition to the flux set up in the armature 8 by thewind ing 7. Sincethe current: traversing the winding 12 prevents the flux set up by thewinding? from traversing the armature 8, this flux will be divertedthrough the leg 15 of the core member 5 and across the air gap 6 andthuspermitthe spring 11 to quickly move the armature and. consequently,the circuit interrupter 3, to open position.

It will be understood that the function of the winding 12 is not toneutralize the flux set up by the winding 7, but merely to so divert thesame through' another' path that the time of operation ofthe interrupterwill be reduced to a minimum ivalue. It will further be understood thatthe-winding 12 onar y magis so, quickly energized, by reason of thequick change in voltage when a fault ob tains on the circuit 1, that theinterrupter 3 may be opened substantially in anticipation of anactualoverload on the circuit.

Our invention is not limited to the particulzir SllHCtlll'GS orarrangementillustrated, as it may be variously modified withoutdeparting from the spirit and scope of the in- YClilllOn, as set forthin the appended claims.

\Ve claim as our invention:

1. In a direct-current circuit, the combination with a circuitinterrupter, of electromagnetic means for holding the interrupterclosed, and means dependent only upon a quick change of current in thecircuit for so shifting the flux of the electromagnetic means that theinterrupter is quickly opened.

2. In a direct-current circuit-,the combination with a circuitinterrupter, of an electromagnetic device energized by a potentialwinding fol-holding the interrupter closed, and means ener ized from thecircuit only upon a quick change of current in the circuit for soshifting the flux'of the eIe'c-trmnagnetic device that the interrupteris permitted to openiquic'kly. I a

3. In a direct-current circuit, the combination with $1 circuitinterrupter, of an electromagnet having twop'aral lel magnetic pathsadapted to hold the interrupter in its closed position, and meansdependent upon the rate of change of current in the circuit and associated'w'ith one'of the p'aths'for causing the fiu'x'to traverse theother path.

4.- In an electric 'circuit,*the combination with a circuit interrupter,of an electromagnet comprising a stationary magnetizable coremember,'ai'i armature, a potential windin for actuating the armature to'holdt-he in arruptr closed, and a; winding energized (in anticipation)of a rush of current in the circuit for reventing the flux from thepotential Winding from actuating 'the armatum 5- The cmritimticu With acircuit interrupter, of an electromagnet having a par tially cios'edmagnetic circuit,- an armature normally completing the magnetic circuitfor holding the'interrupter closed, means for energiiing theelectromagnet, and fneans energized upon a relatively quick change inthe current in the interrupter t Prevent the flux Set up by theenergizing means from traversing the armature.

6. The cmhb'ination with a; circuit Interrupter, of anelectromagnetcomprising a core member having an air ap therein, anarmature normally bridging-the air gap for holding the interrupter'itiits closed position, a winding for energizing the electrqmagnct, and awinding disposed iiroundthe armature to oppose the flow of magneticlinestlie're through from the core member only when a sudden overloadtraverses t e i terrupter.

7. In an electric circuit, the combination with a circuit interrupter,of an electromagnet having 5) potential winding operatiyely connected tothe circuit for holding the interrupter closed, and meanstipraiiii'ely'con nected to the circuit and depeiidentiip'en the changeof current in the circuit, for demagnctizing a portion of theelectroiuagnet 8. In an electric circuit, the combination with a circuitinterrupter, of an electromagnet comprising an armature for directlyactuating the interrupter, a potential Winding for actuating thearmature, and means dependent upon the rate of change of current in thecircuit, for rendering 'the' armature non-responsive to the potentialwindmg.

9. In an electric circuit, the combination with a circuit interrupter,of an electromagnet comprising an armature for directly actuating theinterrupter, a potential wind-V mg for actuating the armature in onedirection', aspring for actuating the armature in the other direction,and means dependent upon the rate'of ch-ange'of current in the circuit,for rendering the armature non-respon'sive to the potential winding.

10. In an electric circuit, the combination, with a circuit interrupter,of an electromagnet comprising an armature for directly actuating theinterrupter, a potential Wind'- ing for actuating the armature in onedirec tion, a spring for actuating the armature in the other direction,an'd means for rendering the armature non-responsive to the potentialwinding only when the current traversing the circuit increases quickly.

lli In a direct-current circuit, the combina-tion with a circuitinterrupter, of an electromagnet comprising an armature for holding theinterrupter closed, a spring for opening the interrupter, a winding foractuat-ing tlie'annature to its closed position, and a winding adaptedto be energized from the circuit only when the current traversing thecircuit changes quickly to so demagnetize the armature as to permit thespring to open the interrupter quickly.

12. In an electric circuit, the combination with a circuit interrupter,of an electromagnet comprising a core member and an arniire ture member,means for energizing the core member and means disposed around thearmature member for deflecting the magnetic flux therefrom inanticipation of a sudden overload on the circuit.

13-. In an electric circuit, the combination with a circuit interrupter,of an electromagnct for holding the interrupter closed, and meansdependentupon the rate of change in the condition of the circuit for sodecreasing the holding effect of the flux of the magnet withoutmaterially afiecting the density thereof as to permit the interrupter tobe actuated; I

14. 'In an electric circuit, the combination with a circuit interrupter,of an electromagnt for holding the interrupter closed, and meansenergized upon a sudden change in the condition of the circuit and inantici ation of a rush of current for so decreasing the holding effectof the flux of the magnet without materially affecting the densitythereof as to permit the interrupter to be actuated.

15. In an electric circuit, the combination with a circuit interrupter,of a magnet and an armature therefor for holding the interrupter closed,and means responsive only to sudden changes in the condition of thecircuit for so deflecting the magnetic flux of the magnet from thearmature as to decrease the holding effect of the magnet and permit theinterrupter to be actuated.

16. In a direct-current circuit, the combination with a circuitinterrupter, of an electromagnetic device for holding the interrupterclosed, and means energized from the circuit in anticipation of a rushof current therein for so shifting the flux of the electromagneticdevice that the interrupter is permitted to open quickly.

17. In an electric circuit, the combination with a circuit interrupter,of a magnet and an armature therefor for holding the interrupter closed,and means associated with the armature member and responsive only tosudden changes in the condition of the circuit for so deflecting themagnetic flux of the magnet from the armature as to decrease the holdingeffect of the magnet and permit the interrupter to be actuated.

18. In an electric circuit, the combination with a circuit interrupter,of an electromagnet comprising a stationary magnetizable core member, anarmature, a potential winding for actuating the armature to hold theinterrupter closed, and a winding energized in anticipation of apredetermined flow of current in the circuit for preventing the fluxfrom the potential winding from actuating the armature.

19. The combination with an electric circuit, of electromagneticcircuit-controlling means and means dependent only upon a quick changeof current in the circuit for so shifting the flux of theelectromagnetic means as to cause an actuation thereof.

20. The combination with an electric circuit, of electromagnetic meansfor controlling the same and means dependent only upon a quick change ofcurrent in the circuit for so shifting the flux of the electromagneticmeans as to cause an actuation thereof.

21. The combination with an electric circuit, of electromagneticcircuit-controlling means and means dependent upon the rate of change ofcurrent in the circuit for so shifting the flux of the electromagneticmeans as to cause an actuation thereof.

22. The combination with an electric circuit, of electromagneticcircuit-controlling means and means energized in antici ation of a rushof current in the circuit or so shifting the flux of the electromagneticmeans as to cause an actuation thereof.

In testimony whereof, we have hereunto subscribed our names this 26thday of Sept, 1918.

CHARLES LE G. FORTES CUE. FREDERIC C. HANKER.

